Durable steel leg curl extension machine built for heavy training with a load capacity up to 600 pounds, delivering sturdy, long-lasting performance for demanding leg work. Compatibility and mounting - Designed to be mounted on a power rack and fits racks with 0.6 in / 0.7 in / 1 in hole sizes - Compatible with barbell plates that have a diameter of 1 in or 2 in (5 cm) - Make sure your fitness rack has penetrating holes before you buy this product Eight adjustable positions - Seated leg extension and curl attachment offers eight height positions to match individual training requirements - Allows a custom fit for each user during muscle group training - Ideal for strengthening triceps, biceps, chest, shoulder and back muscles Sitting leg extender and curl machine - Breaks the traditional bench leg extension design with a removable, adjustable, easy-to-store solution - Small and lightweight to save space while effectively training leg muscle groups - Includes mounting screws and bolts for easy installation Use scenarios - Attach to a power rack for seated leg extensions and curls during leg day in a home gym or studio - Use in a space-limited setup to add leg training without committing full bench space - Accommodate multiple users by adjusting height with the 8-position system for different statures and goals